Frictional locking buckle



Oct. 31, 1950 J. R. c. QUILTER 2,528,078

FRICTIONAL LOCKING BUCKLE Filed Sept. 4, 1946 L; J j mranfior Jamv Amy/170A aw 35W Quartz;

Patented Oct. 3T, 1950 FRICTIONAL LOCKING BUCKLE John Raymond Cuthbert Quilter, Woking, England Application September 4, 1946, Serial No. 694,791 In Great Britain October 1, 1945 This invention relates to buckles for straps and the like.

The main object of the invention is to provide an improved buckle of the frictional type whereby the strap may be quickly tightened by pullin its free end throughthe buckle and a firm grip produced by the frictional locking action as soon as the free end is released.

In these frictional buckles, the strap passes over a rigid portion of the frame and around a parallel bar capable of Sliding in relation thereto, the tension of the strap when tightened holding the bar towards the rigid frame portion, with the free end gripped between them. The sliding bar is usually knurled in order to increase its gripping power, and is guided by slots or the like at the ends of the frame, the extremities of the bar being flattened to engage in these slots; under heavy loads the bar has been found to rock and roll over like a pulley in engagement with the strap and even to burst the retaining slots in which its extremities are guided.

One of the objects of the invention is to pre vent such rocking and rolling of the sliding friction bar, even with heavily loaded straps such as employed in connection with parachute packs.

Another object is to provide the sliding friction bar with extremital shoes of sufficient length in relation to their co-operating guides to restrain the rocking tendency and to distribute the forces over a considerable area of the guides.

A further object is to provide the buckle frame with a bar-guiding member rigidly attached to the frame, paralle1 portions of the respective members affording between them spaces or slots scription of a preferred embodiment, given with 1 reference to the accompanying drawings in which;

Figure 1 is a front elevation of the improved buckle, showing in dot-and-dash lines the strap loosely engaged therewith.

Figure 2 is a vertical sectional view on the line 22 of Figure 1, showing in full lines the strap pulled tight.

Figures 3, 4 and 5 represent, respectively a front elevation, an inverted plan View, and a leftend view of the sliding bar.

Figures 6, 7 and 8 represent, respectively, a front elevation of the guide member, a plan view of the guide member and a vertical section on line 88 of Figure 6.

2 Claims. (Cl. 24171) Figures 9, 10, and 11 represent, respectively, a front elevation of the buckle frame, a vertical section on the line I 0-H) of Figure 9 and a horizontal section on the line I I-l l of Figure 9.

As illustrated in Figs. 1 and 2, the buckle comprises a sliding bar I l, a guide member l2 and a frame [3, these parts being shown separately in detail in Figs. 3 to 11. A strap I4 or the like, shown in dotted lines in Fig. 1, passes in a loop around the bar I I, its tension holding the bar towardsthe upper side or cross bar l5 of the frame with the free end [6 of the strap gripped between them, as shown in Fig. 2; the normal position of the bar I l, resting on the frame when the buckle is assembled and before fitting the strap [4 in place, is shown in dotted lines in that figure.

The sliding bar H is provided with extremital shoes ll, adapted to slide along the ends l8 of the frame; these shoes are integral with the bar, the

extremities being thus of T-shape, as seen in Fig. 3, and the length of the shoes or cross-bars of the T-pieces may be, for example, two or three times the diameter of the knurled middle portion of the bar. Preferably the shoes I! are slightly offset from the axis of the bar, as shown in Figs. 4 and 5; the purpose of the offset is to maintain the bar partly within the opening of the frame 13, so as to overlap the upper and lower sides of the frame at the respective ends of its movement, thus preventing it from falling out of position before the strap is inserted. The shoes may also be bevelled at at one corner 19, as shown in Fig, 5, to match a corresponding bevel in the guide member, as mentioned below.

The guide member l2 consists of a metal shell or stamping of a channel shape, as seen in Fig. 6, corresponding to the ends it and one side of a rectangular buckle frame; the ends of the guide member form uprights of angle section, as seen in Fig. '7, with flanges 20 fitting upon the ends [8 of the frame, to which they are secured by rivets 2| parallel to the axis of the bar H. The other flanges 22 of the guide ends are spaced. from the frame ends I8, these spaces forming parallel slots 23, as seen in Fig. 2, in which the shoes I! of the sliding bar are engaged. The middle portion 24 of the guide member may be of Z-section, with parallel or inclined flanges, the web 25'being secured to the lower side or crossbar 26 of the frame by rivets 2'! perpendicular to the axis of the sliding bar; the outwardly projecting flange 28 is slotted at 29 for attachment of the buckle to a support, such as a looped strap, webbing or the like (not shown). The other flange 30, which is continuous with the free flanges 22 of the end portions or uprights, may either extend in the same plane as those flanges or be set at bevel angle of 45 degrees thereto, as shown, corre' sponding to the bevelling of the shoes H at their corners 19, as mentioned above; the bevelling of these parts provides a more convenient shape of the buckle adjacent to its slotted connection 29.

The buckle frame 13 is shown in Fig. 9 as being of open rectangular shape, the ends is and one side 26 being drilled and countersunk at 31 to receive the rivets 2|, 2'! securing the guide member l2 thereto; the ends l8 and sides I5, 26 will be rounded internally, as seen in Figs. 10 and 11, but the ends and the side 25 are sharp-cornered on their external faces to provide a firm seating for the guide member l2, and the external end faces may he stepped to form shoulders 32 fitting over the ends of the guide member flanges 20 riveted to these faces.

In operation, the shoes or T-shaped pieces H at the extremities of the bar H will slide in the spaces or slots 23 afforded between the fiat ends I8 of the frame (3 andthe free flange edges 22 of the end portions of the guide members I2, the contacting surfaces being of sufficient area to withstand wear and the length of the shoes H being such that they can resist the tendency of the bar H to rock or roll over under the force exerted bythe strap 14 or the like passing around it.

The slotted attachment 29 may be dispensed with in cases where the buckle is employed for adjustment of leg strap or the like, in which case the upper side iii of the frame may be engaged by a looped portion of a connector strap or the like, the adjustable leg strap or the like being looped around the sliding bar I! in a direction to pull down against the opposite side 25 of the frame, this leg strap extending out of the frame at the face remote from the guide member l2 and the pull upon the leg strap tending to draw the shoes I! down the slots 23, instead of up the slots as in the construction illustrated.

What I claim is:

1. In a buckle of the frictional locking type, having an open rectangular frame and a round friction bar in sliding relation to said frame, the combination of a pair of parallel shoes integral with the extremities of said bar, and a guide member for said shoes, said guide member including angle-section flanged portions parallel with the ends of said frame, one flange of each said portion being secured to an end of said frame and the other flange being spaced therefrom, and said shoes being slidably engaged in the spaces between said frame ends and said other flanges.

2. A frictional locking buckle, comprising an apertured rectangular frame having two parallel ends and upper and lower crossbars connecting said ends, a separate member of channel shape having a bottom portion and two flanged uprights, said bottom portion being secured to said lower crossbar, said uprights being secured to said ends with their flanges spaced from said ends to provide parallel slots, and a slidable locking bar having extremital shoes engaged in said parallel slots between said ends and said uprights.

JOHN RAYMOND CUTI-IBERT QUILTER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,416,892 Shields May 23, 1922 1,481,025 Prentice Jan.'15, 1924 1,873,371 Ford Aug. 25, 1932 2,156,870 Rineer et a1 May 2, 1939 2,249,409 White July 15, 1941 

